(a). Field of the Invention
The present invention relates in general to electronic circuits, and more particularly to amplifying circuits with a variable supply voltage.
(b). Description of the Prior Arts
Amplifiers are very common circuit components. However, most amplifiers do not utilize power efficiently. In general, only a part of the energy provided to an amplifier will be used to drive the amplifier outputting an output signal according to an input signal. Most of the energy is wasted.